1. Field of the Invention
The present invention relates to an elastic sheet which is a part of an absorbent product for receiving excrement from a wearer, and to a method of manufacturing the elastic sheet, and also relates to an absorbent product having the elastic sheet.
2. Description of the Background Art
In an absorbent product such as a disposal diaper (i.e. a disposable diaper) for receiving excrement from a wearer, elasticity has been conventionally applied to various portions in order to improve fitting to the wearer or improve an appearance of the absorbent product. For example, in a pants-type disposal diaper, waist opening gathers, leg opening gathers and the like with elasticity are provided, and elasticity is also applied to a front part and a back part located on a stomach side and a back side of the wearer.
A pants-type absorbent product in Japanese Patent Application Laid-Open No. 2000-140021 (Document 1) discloses a technique for favorably fitting an absorbent to a crotch part of a wearer, where a plurality of absorbent part elastic members which are linearly arranged in parallel with a direction perpendicular to a longitudinal direction of an absorbent core are disposed on a back sheet between right and left leg opening edges at a position corresponding to the crotch part, with crossing the absorbent core and leg elastic members on right and left sides of the absorbent core.
Japanese Patent Application Laid-Open No. 2006-122456 (Document 2) discloses a pants-type paper diaper where a rectangular sheet part is attached on each of end portions in a longitudinal direction of an absorbent, and right and left ends of two sheet parts are bonded to form the paper diaper. In the paper diaper, it is proposed that a plurality of first rubber threads which are arranged almost in parallel with a direction of waistline of a wearer (i.e., a horizontal direction) and a plurality of second rubber threads which are arranged so as to cross the first rubber threads, are provided in each of the sheet parts facing the waistline, and thereby the sheet parts contract not only in the direction of the waistline but also in a direction crossing the direction of the waistline, to improve fitting around wearer's legs.
In the absorbent products of Documents 1 and 2, however, since elastic members extending in different directions cross in the vicinity of leg openings, there is a possibility that a sheet member close to a crossing part contracts in two directions to become rigid and the legs of the wearer are strongly compressed. Flexibility in the vicinity of the leg openings is decreased and the legs of the wearer might not be smoothly inserted into the leg openings in wearing the absorbent product, which decreases the comfort of the wearer. Further, in the pants-type paper diaper of Document 2, since the elastic members cross in portions overlapping with the absorbent, twist of the absorbent occurs.